One vertex per element, one color per generator, with an edge from x to x·s.
(9,10)(11,15)(12,16)(13,14)(17,20)(18,22)(19,21)(23,24)(25,26,30,34,29,31,42,45)(27,35,38,44,36,49,43,32)(28,39,41,55,40,33,47,48)(37,52,53,46,51,50,56,54)(1,2)(3,6)(4,5)(7,8)(10,14)(12,19)(15,20)(18,23)(26,31)(27,36)(28,40)(34,45)(38,43)(41,47)(46,54)(50,52) involution — undirected(2,5)(3,7)(9,11)(10,15)(12,18)(13,17)(14,20)(16,22)(19,23)(21,24)(25,27,29,36)(26,32,31,44)(28,37,40,51)(30,43,42,38)(33,46,39,54)(34,49,45,35)(41,56,47,53)(48,52,55,50)(1,3,4,7)(2,6,5,8)(10,14)(11,17)(16,21)(18,23)(25,28,29,40)(26,33,31,39)(27,37,36,51)(30,41,42,47)(32,46,44,54)(34,48,45,55)(35,50,49,52)(38,53,43,56)(2,5)(6,8)(9,12,13,19)(10,16,14,21)(11,18,17,23)(15,22,20,24)(26,31)(28,40)(32,44)(34,45)(35,49)(37,51)(41,47)(53,56)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.